Key Points
Currently, it is difficult to diagnose Alzheimer's without symptoms.
This delays early treatments for the disease and medical and lifestyle preparations.
New blood tests could be possible following new research.
The seeds of Alzheimer's are planted years, even decades before symptoms arise and the disease is diagnosed. At that point, the best treatment options slow the further progression of symptoms.
Those seeds are amyloid beta proteins that misfold and clump together, forming small aggregates called oligomers. Over time, through a process scientists are still trying to understand, those "toxic" oligomers of amyloid beta are thought to develop into Alzheimer's.
What clinicians and researchers have wanted is a reliable diagnostic test for Alzheimer's disease — one that can detect signs of the disease before symptoms, such as cognitive impairment, happens.
University of Washington researchers have taken a big step towards that, having developed a laboratory test that can measure levels of amyloid beta oligomers in blood samples.
Finding patients earlier in the course of their disease will give them time to prepare and make changes that could help them later, explained senior study author Valerie Daggett, a professor of bioengineering at the University of Washington.
"For early treatment, we first need an early diagnosis," she said in an interview. "Also, with an early diagnosis there are lifestyle modifications that can prove helpful and buy time for other therapeutics to come on the market," Professor Daggett told the Australian Financial Review.
The new test — known by the acronym SOBA — could detect oligomers in the blood of patients with Alzheimer's disease.
The team tested SOBA on blood samples from 310 research subjects who had previously made their blood samples and some of their medical records available for Alzheimer's research. At the time the blood samples had been taken, the subjects were recorded as having no signs of cognitive impairment, mild cognitive impairment, Alzheimer's disease, or another form of dementia.
Professor Daggett's team is working to develop SOBA into a diagnostic test for oligomers. In the study, the team also showed that SOBA could be modified to detect toxic oligomers of another type of protein associated with Parkinson's disease and Lewy body dementia.
"We are finding that many human diseases are associated with the accumulation of toxic oligomers that form these alpha sheet structures," Professor Daggett said.
"Not just Alzheimer's, but also Parkinson's, type 2 diabetes and more. SOBA is picking up that unique alpha sheet structure, so we hope this method can help in diagnosing and studying many other protein misfolding diseases."
The researchers say the test does not require sophisticated equipment and does not need to account for things such as age and other risk factors.
That would make it easy to use in standard labs and clinics, although it is not known when it might be available.
"We don't know the cost yet, but our goal is an affordable test that can be deployed on a global scale," Professor Daggett said.
